Drafting-board



S. E. WILLIAMS. DRAFTING BOARD. APPLICATION nuso AUG. 27. 1917.

Patented July 20, 1920.

/N VE N TOR S'faml ey E. Williams ATTORNEY PATENT OFFICE.

STANLEY E. WILLIAM S, OF SAN FRANCISCO, CALIFORNIA.

DRAFTING-BOARD.

Specification of Letters Patent.

Patented July 20, 1920.

Application filed August 27, 1917. Serial No. 188,354.

To all whom it may concern:

Be it lmown that I, STANLEY E. WIL- LIAMS, a citizen of the United States, and a resident of the city and county of San Francisco, State of California, have made a new and useful Invention in Drafting- Boards; and I do hereby declare the following to be a full, clear, concise, and exact description ofthe same. I

The invention relates particularly to means for securing drawing paper to drafting boards.

Among the objects of this invention are to provide suitable mechanical clamps attachable to the lateral edges of drawing boards for the purpose of securing the drawing paper thereon, smooth and taut; that will provide a working straight edge on opposite ends of the drawing board, which may be adjusted for squaring up the board; with a further object that the working edge of the board may be extended beyond the limit of the drafting board to support the head of the T square. Other objects and advantages will appear as this description progresses. V I

In this specification and the annexed drawings, the invention is illustrated in the form considered to be the best, but it is to be understood that the invention is not limited to such form because it may be embodied in other forms, and it is also to be understood, that in and by the claims following the description, it is desired to cover the invention in whatever form it may be embodied. i r

In the accompanying one sheet of draw- Figure 1 is a plan view of a drafting board having this invention applied thereto, certain of the parts being shown in cross-section to disclose the underlying structure.

Fig. 2 is a fragmentary enlarged detail of one edge of the board, in cross section taken on the line II-II in Fig. 1.

Fig. 3 is a similar view illustrating a modified type of clamp, taken on line III-III of Fig. 1.

Fig. 4 is a similar view of the same in cross-section taken on the line IV-IV, Fig. 3.

Fig. 5 is a similar view in detail illustrating the end guides for the end of the clamps.

In detail, the construction illustrated in the drawings includes: the conventional drawing board 1 having one or both ends provided with the strips 2 and 3, fixed thereto by the dowel screws 44 passing through the strip and screwed in to the ends of the drawing board; the tops ofthe strips 2 and 3 being flush with the plane of the drawing board. The strips are identical on both sides of the board and preferably consist of a strip of hard wood routed out on its lower inner corner to provide a recess for the clamping jaws 5 and 6 laterally movable therein. For economy in construction, the ends of the clamping jaws may be grooved to engage the body of the screws 4-4 as illustrated in Fig. 5, whereby the clamps are held in position and guided in their lateral movement to and from the ends of the drafting board. There the cost will justify, the metal guide strip 7 may be interposed between the ends of the jaws and screws 4. Various means are available for advancing and retracting the jaws 5 and 6,tw0 desirable means being illustrated in the drawing, that on the left consisting of a screw 7 threaded'into the strip 2 and provided with a knurled head 8, the inner end of the screw bearing against the central portion of the jaw 5 which is reinforced by a metal plate 9 for the end of the screw 7 to bear against. The head 8 is located below the level of the head of the T square when the blade of the T square is resting upon the surface of the drawing board.

An alternative construction is illustrated on the right hand side-of Figs. 1, 3 and 4, in whichthe eccentric 10 pivoted on the pin 11 bears against the jaw 6, the clamp like action of the eccentric forcing the jaw 6 forward when the eccentric is swung by its convenient handle 12. The recess 13 is provided in the edge of the strip 3 into which the handle 12 may be swung, to leave a flush unobstructed working edge on the strip 3 for the head of the T square, as illustrated in dotted lines in Fig. 4.

To prevent creasing the paper where it folds over the edge of the drawing board 1, the edge of the board may be rounded as at 14 where the board is constructed complete, in accordance with this invention. Where the end assemblies are made up for attachment to old drawing boards, this rounded edge may be attached to the strips 2 and 3 in the form of a molding, having a rounded edge, as indicated at 15 and 16 (see Figs. 2 and 3), this molding being interposed be- V tween the strips 2 and 3 and the ends of the drawing board and securely held by the screws, 4:. The working end of the board can be squared by inserting shims between the'ends of the strips 2 and 3 adja- V and top'artially expose said dowel members,

cent to the screws 4 where required.

This invention is operated substantially as follows: proper length 17 (see Fig. 3) is laid upon the plane of the board and the ends of the paper'are threaded down through the slots 18 and 19,between the clamp jaws 5 and 6 and the adjacent ends of the board 1. The

clamping means such as 7 'and 10 are then operatedto force the aws 5 and 6 against the paper, securely clamping it between the jaws'5 and 6 and the ends of the board. This is best accomplished by tightening one jawfirst, then smoothing the paper on the board and taking 'up the slack therein be-' fore setting the other jaw. This means of holding the paper on the drawing board obviates the necessity of thumb tacks and other exposed means interfering with the proper operation of the T square, angles and other instruments in use by the draftsman. I

'A further advantage of this system is that (it permits the use of a continuous sheet of drawing paper "17, by mounting the rollof paper beneath the drawing board in any suitable manner, threading the ends up through the slot 18, across the surface of the board and down through the slot 19. Inthis manner, a drawing of any length can be made and traced. without cutting the paper and bythe use of a drawing board of'thenormal size. I

Having thus described this invention, whatI claim and desire to secure by Letters Patent is:

1. A drawing board; end strips fixed to the ends of said board by dowels and having slots betweensaid dowels; paper clamping jaws movable in said strips across said slots and engaging said dowels, whereby the strips are guidedin their movement; and adjusting means in said strips engaging said jaws. 7

2. A device of the character described comprising a drawing board, a strip ar The strip of paper of the I ranged at oneend of said board and attached thereto by dowel members passing through the ends," the edge of said strip contiguous to the board being cut away between said dowel members to provide a slot clamping means within the cut-away portion and movable. across said slot, said clamping means engaging the exposed portions of said dowel members, whereby they are guided in their movement, and means on saidstrip for adjusting said clamping IIIGELIIS."

3. A. device of the, character" described comprising a drawing board, a strip 'arranged at one end of said board and attached thereto by dowel members passing through its ends, the edge of saidstrip con-' 'tiguous to the board being cut-away between said dowel members to 'form an elongated slot partially exposing said dowel members and being also formed with a recess, a

clamping bar in said recess and movable across said slot, the ends of said bar engaging and beingeng'aged by said dowel members,and means on theouter edge of said strip foradjusting saidbar.

4; An attachment for drawing boards comprising a stripmember having one edge cut away between its ends, clampmg means on said strip'movab'le across said cut-away portions, means for securing the ends of said cut-away edge to one end of a drawing board',"and means 'on'said'strip for movably adjusting saidclamping means;

5. An attachment for drawing iboardsr comprising a strip'member having onefedge cut away between its ends and also provided with a recess, a clamping bar in said recess movable across said cut-away portion, means for securing the ends'of said'cut-away edge 'to one end of-a'dra'wing board, and means on the opposite edge of the strip for adjusting said bar. v

In testimony whereof, I have hereunto set myhand at San Francisco, California,

day of Aiwust, 1917. 'STANfiEY E. WILLIAMS. In presence of-- g A; J. HENRY, V

LINCOLN V. J OI-INSON.

this 20th 

